I too have an Oracle and they're a lot better than some folks make them out to be. Changed out the Handguard also to a Quad, and lots of other items.
There's nothing wrong with Nikon. I have a Buckmaster model on a butt kicking 30-06 and it's been great. Not let me down in 7yrs. Always 4-shot MOA or better @100yds using 150gr Corlokt ammo.
Anyway, what I have on my Oracle is I use a couple Scopes. One is a Bushnell RD TRS-32(holds POI very well).
Recently I switched to a Bushnell 1-4x24 w/BDC. I liked this Scope over the "Throw Down" model better.
You said 1-4x30 Scope, so I don't know if this is same Scope you're looking at?
It has clear/crisp Glass out to edge. Tight Magnification Ring, but I like that(won't shift under any recoil or bumping against anything). Fast Focus Eye Piece. Positive Click Knob Adjustments. Haven't tried it out yet as Weather's been a little extreme for me(dam age) to want to venture out in sub-cold temps to try it out.
I mounted it using Millet 30mm Tactical Mount that cantilever's out to keep Eye Piece at a distance, and to get good access to the Charge Handle.
I looked at the Nikon P223 3-fixed Scope and really liked it, until I saw that Bushnell was coming out with the 1-4 Scope that gives a person better option of easier close range with 1 power and better 4 power on top end for further shots, instead of just a fixed 3-power that would be very blurry in Brush Hunting conditions or CQD.